NAIROBI (Thomson Reuters Foundation) - Rashid Hassan Mohammed began using drugs when he was 15, after fleeing an abusive home in the Kenyan coastal city of Mombasa and joining a street gang that robbed and stole to buy heroin.
He was diagnosed with HIV in 2014 and realized that he needed to give up drugs after years of sharing needles with fellow addicts.
"I didn't think that when you inject, or share the same injection with your friend, it may cause HIV," said Mohammed, 34, who has been receiving methadone treatment for a year to wean his body off heroin.
"I thought it was only sex."
The number of Kenyans injecting heroin has surged in recent years as the East African nation has become a major transit route for international drug cartels moving heroin from Afghanistan to Europe, experts say.
Narcotics have spilled on to the local market, where people are largely unaware that injecting drugs can lead to HIV infection, sparking concerns that Kenya's success in tackling HIV could be reversed.
"The numbers (of users) are increasing both along the coast and in Nairobi and there is evidence that it is also spreading out to places like Kisumu," said Calleb Angira, director of the Nairobi Outreach Services Trust (NOSET), who has worked with addicts for almost 30 years.
"That is because the interventions we have are not enough," said Angira, who set up NOSET in 2005 to offer HIV prevention and treatment services to drug users in Ngara, an estate outside Nairobi's city center.
Over the past 20 years, Kenya has slashed its HIV prevalence rate to 6 percent today from 11 percent in 1996 through campaigns to encourage safer sex between heterosexual couples and improved access to antiretroviral drugs, according to the United Nations Programme on HIV/AIDS (UNAIDS).
But little has been done in Kenya to reduce the risk to injecting drug users, sex workers and men who have sex with men, who together make up more than 30 percent of new infections, government data shows.
HIV prevalence among injecting drug users is around 18 percent - three times the national prevalence rate - and around 4 percent of new HIV infections occur among people who inject drugs, government figures show.
Kenya had 18,000 injecting drug users in 2011, according to government statistics.
"The majority of injectors worldwide are young men," said Chris Beyrer, president of the International AIDS Society.
"This is a sexually active population and very often their wives, girlfriends, female partners are very much at risk."
Injecting drug users need easy access to sterile needles to make their habits safer, opiate substitutes to help them stop injecting and HIV testing and treatment, experts say.
But stigma and punitive laws often mean they are mistreated or turned away when they seek services, according to UNAIDS.
"Society rejects them," Angira told the Thomson Reuters Foundation. "Even their families reject them. They're isolated. They're criminalized. They're seen as hopeless people."
Drug users fear asking for clean needles, as this can lead to police harassment or criminal prosecution.
Governments and donors are also reluctant to fund these services because of a false belief that they condone drug use and encourage illegal behavior, Beyrer said.
"Despite the evidence that shows very clearly that providing sterile injecting equipment does not encourage people to inject, it's a widely held view that what we should be doing is stopping injecting drug use," he said.
Kenya was slow to initiate programs for injecting drug users, but recognized the need for specialized services after some 100 addicts died from withdrawal during a 2011 heroin shortage, triggered by a crackdown on drug barons.
Addicts came out from the shadows seeking help.
"We realized that we didn't have the capacity as government to provide treatment," said Helgar Musyoki, a program manager with Kenya's National AIDS and STI Control Programme (NASCOP).
"We learned our lesson."
In 2013, the government approved its first needle and syringe program. Funded with donor money, it provides drug users with clean, free equipment to reduce the transmission of HIV and other diseases.
The government has not put any of its own money into these services but has allowed donors to open seven needle and syringe programs in its two largest cities.
More are needed, experts said.
"What the needle and syringe program did was to bring them (drug users) out very clearly, knowing that the program was actually targeting them," said Angira of NOSET.
"They came and said: 'I'm injecting' and that made them access other services like HIV testing."
The government opened its first clinic providing oral heroin substitutes in 2014, and has pledged to treat 2,000 patients over two years.
Three methadone clinics are operating in Kenya, with another three scheduled to open in August. It also plans to equip three mobile vans with methadone to reach injecting drug users across the country.
NOSET staff says that even the limited services offered to injecting drug users are having an impact.
"With the interventions, the (HIV) rates are going down,” said Nancy Ndwiga, who oversees NOSET's HIV treatment.
More funding is needed for services and to train heath workers to provide services to injecting drug users.
"This is a new route of HIV transmission. There's not a lot of people in any African country with experience (of it)," said Beyrer.
Former heroin users like Mohammed are grateful for the services that exist for injecting drug users.
"They (NOSET) saved my life," he said.
Although he has been clean for over a year, he has yet to contact his family who he has not seen since he left home.
"It's not easy to be trusted, but I know one day I will earn their trust again."
(Editing by Katy Migiro and Katie Nguyen.; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women’s rights, trafficking, property rights and climate change. Visit news.trust.org to see more stories.)